Unreviewed gardening. Marking webaudio/automatic-pull-node.html as
[ Pass Slow ] instead of [ Pass Timeout ] for XP.

* platform/chromium/TestExpectations:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@138714 268f45cc-cd09-0410-ab3c-d52691b4dbfc
[Qt] Fix a crash when the QQuickWebPage is destroyed between the scene graph sync and render.
https://bugs.webkit.org/show_bug.cgi?id=106018

Reviewed by Simon Hausmann.

The main and rendering threads are only guaranteed to be synchronised in
the updatePaintNode call. In every other cases, QQuickItems cannot be
safely accessed from the rendering thread.

Do as the first patch version in
https://bugs.webkit.org/show_bug.cgi?id=104574 was doing and copy the
ratio value directly to fix the issue.

Also add a note about the threading issue in QQuickWebPage::updatePaintNode.

* UIProcess/API/qt/qquickwebpage.cpp:
(QQuickWebPage::updatePaintNode):
* UIProcess/qt/QtWebPageSGNode.cpp:
(WebKit::QtWebPageSGNode::QtWebPageSGNode):
* UIProcess/qt/QtWebPageSGNode.h:
(QtWebPageSGNode):
(WebKit::QtWebPageSGNode::devicePixelRatio):
(WebKit::QtWebPageSGNode::setDevicePixelRatio):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@138715 268f45cc-cd09-0410-ab3c-d52691b4dbfc